# Calculate the voltage of a standard cell with the following half-cell reactions

1. I have to calculate the voltage of a standard cell with the following half-cell reactions:

Ni(s) ---> Ni2+ + 2e-
2e- + Cl2(g) ---> 2Cl-

2. By the electrolysis of water, 11.2L of oxygen at STP was prepared
a) What charge was required?
b) If a current of 0.5A was used, how long did it take?

Thanks for the help.

## Answers and Replies

GCT
Homework Helper
what do you need help for??? these are all standard questions, it doesn't get any easier then this. Try solving it yourself first, show your work.

these questions may very well be easy for you..but I am not familiar with calculating voltage and charge.

I dont need the answer, just a helpful hint. (a site, or something..I dont mind doing the work but I dont see any useful info about it in my book)

Last edited:
Gokul43201
Staff Emeritus
Gold Member
I'm sure your text talks about Faraday's Laws of Electrolysis. If not , there's always Google.

GCT
Homework Helper
hint #1

finding the voltage of the standard cell is similar to Hess' law (with the emphasis on "similar"). Perhaps you can remember the method now. What can you do with each of the standard emf values for each half reaction to solve the problem? The question is especially easy since the stoichiometric ratio of electrons are the same.

hint #2

2. By the electrolysis of water, 11.2L of oxygen at STP was prepared
a) What charge was required?
b) If a current of 0.5A was used, how long did it take?
It is quite important that you read up on this subject, it should be at the end of the electrolysis section of your text. First, what can yo do with the 11.2L at STP, how can yo convert this to moles?